US8945431B2 - Intercalation of silicon and/or tin into porous carbon substrates - Google Patents

Intercalation of silicon and/or tin into porous carbon substrates Download PDF

Info

Publication number
US8945431B2
US8945431B2 US13/054,193 US200913054193A US8945431B2 US 8945431 B2 US8945431 B2 US 8945431B2 US 200913054193 A US200913054193 A US 200913054193A US 8945431 B2 US8945431 B2 US 8945431B2
Authority
US
United States
Prior art keywords
silicon
tin
nanoparticles
tin nanoparticles
lithium
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related, expires
Application number
US13/054,193
Other versions
US20110311873A1 (en
Inventor
Christof Schulz
Hartmut Wiggers
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Universitaet Duisburg Essen
Original Assignee
Universitaet Duisburg Essen
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Universitaet Duisburg Essen filed Critical Universitaet Duisburg Essen
Publication of US20110311873A1 publication Critical patent/US20110311873A1/en
Assigned to Universität Duisburg-Essen reassignment Universität Duisburg-Essen ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: SCHULZ, CHRISTOF, DR, WIGGERS, HARTMUT, DR
Application granted granted Critical
Publication of US8945431B2 publication Critical patent/US8945431B2/en
Expired - Fee Related legal-status Critical Current
Adjusted expiration legal-status Critical

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B31/00—
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H01M4/0402—Methods of deposition of the material
    • H01M4/0416—Methods of deposition of the material involving impregnation with a solution, dispersion, paste or dry powder
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H01M4/0471—Processes of manufacture in general involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/133—Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/134—Electrodes based on metals, Si or alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H01M4/1393—Processes of manufacture of electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H01M4/1395—Processes of manufacture of electrodes based on metals, Si or alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
    • H01M4/386—Silicon or alloys based on silicon
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
    • H01M4/387—Tin or alloys based on tin
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • H01M4/587—Carbonaceous material, e.g. graphite-intercalation compounds or CFx for inserting or intercalating light metals
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries
    • Y02E60/122—

Definitions

  • the present invention relates to the field of lithium-ion battery technology, in particular anode materials suitable in this regard and their production.
  • the present invention relates in particular to a method for manufacturing an electrically conductive, porous, silicon- and/or tin-containing carbon material as well as the carbon material itself produced in this way and its use in particular for production of anode materials, preferably for lithium-ion batteries.
  • the present invention relates to anode materials containing the carbon material according to the invention and/or using the carbon material according to the invention as well as batteries, in particular lithium-ion batteries comprising these anode materials.
  • Lithium-ion batteries are characterized by very high energy densities. They are thermally stable, supply a constant voltage over the duration of the discharge time and do not have a so-called memory effect. Such batteries are known in the prior art in the form of traditional batteries for a single use as well as in the form of rechargeable batteries.
  • Lithium-ion batteries generate the electromotive force by displacement of lithium ions.
  • positively charged lithium ions migrate through the electrolyte from a cathode between the graphite planes of an anode, while the charging current supplies the electrons over the external circuit, such that the ions form an intercalation compound of the Li x nC type with graphite.
  • the lithium ions migrate back and the electrons can flow over the external circuit to the cathode.
  • intercalation in the sense of the present invention refers to the intercalation of a mobile-guest species into a host lattice without destroying the structural principle of the host substance and/or the host lattice.
  • the host lattices have layered structures, tubular structures or cage structures, for example, in which the guest substance can be intercalated in a one-, two- or three-dimensional arrangement, often with volume expansion.
  • the intercalation of ions is associated with oxidation or reduction of the host lattice.
  • an electronically conductive host as the electrode is anodically or cathodically polarized in the electrolyte, so that anions and/or cations, optionally solvated, move from the electrolyte into the host lattice.
  • This electron/ion transfer reaction results in a mixed conductor, which usually has a better electronic conductivity than the starting material.
  • Electrochemical intercalation reactions are usually reversible and the mobility of the guest ions is high, in particular in host lattices having a layered structure.
  • Intercalation performed in this way includes three basic steps: diffusion or migration of ions, which are usually solvated, to the electrochemical double layer of the host lattice, possible desolvation and subsequent transfer of the ions into free lattice sites near the surface region of the host, and finally, diffusion of the ions into the interior of the lattice.
  • intercalation electrodes for electro-chemical current sources has been attracting great interest again, at the latest since the rapid development of rechargeable lithium cells.
  • Intercalation electrodes have been investigated widely since the 1970s for applications in organic and aqueous electrolyte solutions.
  • reduction of the cathodic oxides takes place by way of the intercalation of a proton in MnO 2 and/or PbO 2 .
  • lithium ion intercalation compounds for example, lamellar carbon, transition metal oxides or metals forming alloys with lithium are used as the negative active compounds which can reversibly take up and release lithium ions.
  • the positive lithium ion charges are neutralized by electron uptake or release by the host material.
  • the theoretical values for the specific charge in use of an inactive host material are usually much lower.
  • lithium activity in the intercalation compounds is lower than that of the metallic lithium, i.e., lower than 1, so the electrode potential is also shifted toward less negative values depending on the charge state.
  • lithium ions which are much smaller are used in lithium ion intercalation compounds.
  • the prerequisite for intercalation of lithium ions in a host lattice material is that the host lattice matrix must be able to allow the uptake of host ions not only sterically but also electronically, i.e., must have a corresponding structure of the energy bands.
  • the active material of the anode of a conventional lithium-ion battery is made of graphite for example.
  • the cathode contains, for example, lithium metal oxides in a layered structured such as lithium cobalt oxide, lithium nickel oxide or the spinel LiMn 2 O 4 .
  • Lithium-ion batteries must be completely anhydrous because otherwise the water can react with the conductive salt (e.g., LiPF 6 ) to form hydrofluoric acid (HF). Therefore a mixture of anhydrous aprotic solvents is usually chosen.
  • lithium-ion batteries usually do not have the so-called memory effect and also have an extremely low spontaneous discharge or none at all.
  • Lithium-ion batteries are able to supply power to portable electronic devices having a high power demand when these devices would be too heavy or too large for traditional lead batteries, for example, cellular telephones, digital cameras, camcorders or laptops as well as electric vehicles and hybrid vehicles. In the model building sector and in electric power tools, they have already become well established.
  • the usable lifetime of lithium-ion batteries is several years, for example, although that depends greatly on the use and storage conditions.
  • silicon especially in particulate form, may be mixed into a carbon or graphite matrix or otherwise introduced, for example, by gas phase deposition or the like (in this regard, cf. also the documents WO 2005/096414 A2, DE 10 2005 011 940 A1, DE 103 53 996 A1, DE 103 53 995 A1 and DE 10 2006 010 862 A1, for example).
  • silicon is mechanically degraded and amorphized due to the volume contraction and expansion which occur during charging and discharge processes and ultimately the silicon is no longer available for storage of lithium due to obviously inferior electrical contacting and destruction.
  • the increasingly inferior electrical contacting is counteracted by the intercalation of silicon in a carbon or graphite matrix.
  • WO 2005/096414 A2 describes an electrode material which is produced by mechanical mixing of particles, carbon black and graphite.
  • a number of disadvantages are associated with the silicon-containing materials proposed as the anode materials for lithium-ion battery in the prior art: a plurality of silicon-containing anode materials proposed in the prior art tend to cause mechanical degradation and amorphization so that ultimately lithium can no longer be stored due to a lack of electrical contacting. Because of the often inadequate porosity of the matrix and host structure, this matrix and/or host structure often suffers irreversible damage due to the volume contraction that occurs in the charging operation. The materials known in the prior art often do not have adequate mechanical properties, in particular do not have the corresponding strengths.
  • the object of the present invention is therefore to provide a material suitable as the anode material for lithium-ion batteries and to provide a corresponding method for producing same, such that the disadvantages of the prior art described above are avoided at least partially or they should at least be diminished.
  • the present invention proposes a method described herein.
  • Additional advantageous embodiments of this aspect of the invention are the subject matter of the subsidiary claims in this regard.
  • the subject matter of the present invention is thus a method for producing an electrically conductive, porous, silicon- and/or tin-containing carbon material which is suitable in particular for producing an anode material, preferably for lithium-ion batteries, such that in a first process step silicon nanoparticles and/or tin nanoparticles and/or silicon/tin nanoparticles are introduced into a matrix based on at least one organic polymer, in particular being dispersed therein, and subsequently in a second process step the polymer matrix obtained in this way and containing the silicon nanoparticles and/or tin nanoparticles and/or silicon/tin nanoparticles is carbonized to carbon.
  • the subject matter of the present invention relates a method for intercalating silicon and tin into porous carbon substrates by the aforementioned process steps.
  • the silicon, tin and/or silicon/tin nanoparticles are preferably introduced and/or intercalated and/or dispersed homogeneously and/or in a uniform distribution in the organic polymer matrix.
  • nanoscale silicon and/or silicon By embedding the silicon and/or tin in a porous carbon matrix, a deterioration of the electrical contacting in particular is also counteracted.
  • the use of nanoscale silicon and/or silicon also makes it possible to effectively counteract destruction of the matrix which occurs due to changes in volume because nanoscale material is much more tolerant in this regard.
  • Embedding nanoscale silicon and/or tin in a porous to highly porous but nevertheless mechanically stable host matrix of carbon ensures on the one hand a good electrical contact between silicon and/or tin and carbon, but on the other hand also allows the silicon and/or tin to “breathe” within this matrix (i.e., allowing free volume expansion due to intercalation of lithium ions in the charging process) because sufficient volume is available due to the high porosity without the host structure being damaged.
  • the materials according to the invention also have excellent mechanical properties in particular with regard to the availability of the expansion volume for the silicon and/or tin but also with regard to the mechanical strength for use as an anode material.
  • a system that is especially stable mechanically and permits adequate volume expansion while on the other hand also having excellent electrical conductivity due to the excellent electrical contact between silicon and/or tin and carbon is made available by intercalation of the silicon, tin and/or silicon/tin nanoparticies in the polymer matrix, in particular by means of in situ polymerization in the presence of the silicon, tin and/or silicon/tin nanoparticies and subsequent carbonization (also referred to by the synonyms “coking,” “pyrolysis,” “burn-off” or the like).
  • the products obtainable according to the invention are suitable in particular for use as silicon- and/or tin-containing anode materials, preferably for lithium-ion batteries, including accumulators, because despite the volume contraction and expansion occurring during the charging and discharging processes, they do not have a tendency to any mentionable mechanical degradation and amorphization of the silicon and/or tin and/or do not have any such tendency at all and an excellent electrical contacting associated with an excellent ability to store lithium ions is preserved. Due to the adequate porosity of the matrix structure and/or host structure, there is also no irreversible damage to this matrix and/or host structure due to the volume contraction occurring in the charging process.
  • the silicon- and/or tin-containing materials obtainable according to the invention have excellent mechanical properties, in particular appropriate strengths with at the same time good availability of the required expansion volume for the silicon and/or tin.
  • the process management according to the invention leads to an electrically conductive porous carbon material with silicon, tin and/or silicon/tin nanoparticies intercalated into them, i.e., the result is thus porous carbon substrates with nanoparticulate silicon and/or tin intercalated therein.
  • these are in particular particles having an average particle size (D 50 ) in particular an average crystallite size (D 50 ) in the range of 1 to 1000 nm in particular 2 to 500 nm, preferably 2 to 250 nm, especially preferably 5 to 100 nm, most especially preferably 5 to 50 nm.
  • Nanoparticles having an average crystallite size between 1 and 100 nm are especially suitable. Nanoparticles having an average crystallite size between 5 and 50 nm are suitable in particular.
  • aggregated silicon is especially suitable, as is also unaggregated silicon (so-called “soft agglomerates”) each with an average crystallite size between 1 and 100 nm. In this case silicon with an average crystallite size between 5 and 50 nm is especially suitable.
  • the aforementioned average particle sizes and/or crystallite sizes can be determined, for example, from histograms of transmission electron micrographs or from x-ray diffractograms as well as—for example, in the case of unaggregated silicon—from the BET surface area.
  • crystalline silicon, tin and/or silicon/tin nanoparticles produced by gas-phase synthesis, microwave plasma synthesis or the like can typically be used for the purposes according to the invention, for example.
  • Suitable silicon, tin and/or silicon/tin nanoparticles, in particular those that are crystalline, can be obtained, for example, in a microwave plasma in the case of silicon nanoparticles starting from silane or in the case of tin nanoparticles starting from stannan or finally in the case of Si/Sn nanoparticles to be used according to the invention, starting from silane/stannan mixtures or silane/tin tetrachloride mixtures.
  • silane/stannan mixtures or silane/tin tetrachloride mixtures silane/stannan mixtures or silane/tin tetrachloride mixtures.
  • the silicon, tin and/or silicon/tin nanoparticles to be used according to the invention are usually embodied in a crystalline form.
  • the degree of crystallinity of the silicon, tin and/or silicon/tin nanoparticles used is advantageously at least 70%, in particular at least 80%, preferably at least 90%, especially preferably at least 95% and most especially preferably the silicon, tin and silicon/tin nanoparticles used are embodied in a completely crystalline form.
  • Silicon, tin and silicon/tin nanoparticles suitable for use according to the invention usually have a PET surface area of 1 to 2000 m 2 /g in particular 10 to 1500 m 2 /g, preferably 25 to 1000 m 2 /g and especially preferably 50 to 600 m 2 /g. All the BET values determined and/or mentioned within the scope of the present invention are determined according to ISO 9277 (1995) which replaces DIN 66131.
  • the silicon nanoparticles used according to the invention may in particular consist of pure silicon but they may also be provided with at least one doping element as described below.
  • the tin nanoparticles used according to the invention may be made or pure tin in particular, but may also be provided with at least one doping element as described below.
  • the silicon/tin nanoparticles used according to the invention may consist in particular of silicon/tin mixtures in any mixing ratio, in particular based on silicon/tin composites or silicon/tin alloys, but the silicon/tin nanoparticles may optionally also be provided with at least doping element, as described below.
  • Nanoparticles based on silicon/tin composites or silicon/tin alloys are preferably used according to the invention. Tin has the advantage of having a good electrical conductivity.
  • the silicon, tin and silicon/tin nanoparticies that are used, in particular crystalline nanoparticles may in particular have a p-type and/or n-type doping, preferably of up to 10 21 /cm 3 , where the doping elements may be selected from Main Groups 3 to 5 of the periodic system of elements (corresponding to groups 13 to 15 of the periodic system of elements according to the new nomenclature) and from elements of the iron group, in particular from the group of boron, aluminum, phosphorus and/or iron as well as mixtures thereof.
  • the silicon, tin and/or silicon/tin nanoparticies may be doped and/or to contain at least one doping element, where this doping element may be selected in particular from the group of phosphorus, arsenic, antimony, boron, aluminum, gallium and/or indium.
  • the amount of silicon, tin and/or silicon/tin nanoparticles used may vary in wide ranges.
  • the silicon, tin and/or silicon/tin nanoparticies are generally used within the scope of the method according to the invention in amounts such that the molar silicon and/or tin content (i.e., the molar silicon, tin and/or silicon/tin nanoparticle content) in the electrically conductive, porous, silicon- and/or tin-containing carbon material amounts to 5 to 90 mol %, in particular 10 to 80 mol %, preferably 20 to 70 mol %, based on the electrically conductive, porous, silicon- and/or tin-containing carbon material.
  • the molar silicon and/or tin content i.e., the molar silicon, tin and/or silicon/tin nanoparticle content
  • the electrically conductive, porous, silicon- and/or tin-containing carbon material amounts to 5 to 90 mol %, in particular 10 to 80 mol %, preferably 20 to 70 mol %, based on the electrically conductive, porous
  • the silicon, tin and/or silicon/tin nanoparticles are used in amounts within the scope of the method according to the invention, such that the silicon and/or tin content based on volume (i.e., the volume-based silicon, tin, and/or silicon/tin nanoparticle content) in the electrically conductive, porous, silicon- and/or tin-containing carbon material amounts to 1 to 60 vol %, in particular 2 to 50 vol %, preferably to 4.0 vol %, based on the electrically conductive, porous, silicon- and/or tin-containing material.
  • volume-based silicon, tin, and/or silicon/tin nanoparticle content in the electrically conductive, porous, silicon- and/or tin-containing carbon material amounts to 1 to 60 vol %, in particular 2 to 50 vol %, preferably to 4.0 vol %, based on the electrically conductive, porous, silicon- and/or tin-containing material.
  • the silicon, tin and/or silicon/tin nanoparticies are typically used in such amounts within the scope of the method according to the invention that the silicon and/or tin content based on mass (i.e., the mass-based silicon, tin and/or silicon/tin nanoparticle content) in the electrically conductive, porous, silicon- and/or tin-containing carbon material is 1 to 70 wt %, in particular 2 to 60 wt %, preferably 5 to 50 wt %, based on the electrically conductive, porous, silicon- and/or tin-containing carbon material.
  • the silicon, tin and/or silicon/tin nanoparticles are advantageously subjected to a surface modification and/or surface functionalization, preferably a hydrophobization prior to being introduced into the organic polymer, in particular before being dispersed in the organic polymer.
  • the surface modification and/or surface functionalization may be performed by alkylsilyl group functionalization, preferably by methylsilyl group functionalization (e.g., trimethylsilyl group functionalization).
  • the functionalization of the surface of nanoparticles the in particular for the purposes of hydrophobization is advantageous to disperse the silicon, in and/or silicon/tin nanoparticles in the polymer and/or the starting monomers in this regard, in particular homogeneously.
  • the organic polymer is created in situ in the presence of the silicon, tin and/or silicon/tin nanoparticies.
  • the silicon, tin and/or silicon/tin nanoparticies which have preferably first been surface modified and/or surface functionalized in particular hydrophobized, are dispersed in the corresponding organic monomers and/or solutions or dispersions thereof and then the organic monomers are subsequently polymerized in the presence of the silicon, tin and/or silicon/tin nanoparticles to form the respective organic polymers.
  • the result is an organic polymer matrix in which the silicon, tin and/or silicon/tin nanoparticles are intercalated and/or embedded, preferably in a homogeneous and/or uniform distribution such that this polymer matrix is then subsequently carbonized and/or pyrolyzed as will be described in detail below.
  • Organic monomers preferred according to this invention are selected in particular from the group of vinyl chloride, styrene, tetrafluoroethylene, ethylene and/or polypropylene, preferably styrene, especially preferably styrene together with divinylbenzene (in the latter case, divinylbenzene-crosslinked polystyrene is formed after polymerization, as will be described below).
  • organic polymers which do not contain any chemically bound oxygen are preferably used as the organic polymers which form the matrix for the silicon, tin and/or silicon/tin nanoparticles to be intercalated therein.
  • Chemically bound oxygen is capable of oxidizing a portion of the silicon, tin and/or silicon/tin nanoparticles to silicon dioxide and/or tin oxide in the subsequent carbonization, but these oxides would then be useless for the application as anode material, in particular for lithium-ion batteries.
  • the organic polymers which form the matrix for the silicon, tin and/or silicon/tin nanoparticles to be intercalated therein are selected in a manner preferred according to the invention from the group of polyvinyl, chloride, polyacrylonitrile, polystyrene, polytetrafluoroethylene, polyethylene and/or polypropylene, preferably polystyrene.
  • Divinylbenzene-cross linked polystyrene is especially preferred, in particular with a divinylbenzene content of 0.1 to 20 wt %, preferably 1 to 10 wt %, based on the organic polymer.
  • the organic monomers and/or the organic polymers are present in sulfonated form and/or contain sulfonic acid groups.
  • the sulfonic acid groups are usually not introduced until after production of the polymer and/or before the process step of carbonization, namely by sulfonation in a known manner. Sulfonic acid groups form free radicals in the subsequent carbonization, leading to the crosslinking which responsible for the good carbon yield in the context of the pyrolysis process.
  • fundamentally other chemically suitable groups may also be used, for example, isocyanate groups.
  • intercalation and/or dispersion of the silicon, tin and/or silicon/tin nanoparticies in the organic monomers and/or polymers this may be performed by those skilled in the art in the usual manner, for example, by stirring, kneading, milling using a ball mill, ultrasonic treatment, extrusion, etc.
  • the polymers containing the silicon, tin and/or silicon/tin nanoparticles may be subjected to a shaping process before the process step of carbonization.
  • the polymers containing silicon, tin and/or silicon/tin nanoparticles may be processed further to molded articles such as spheres, disks, blocks, more complex structures or the like which are subsequently carbonized and/or pyrolyzed so that carbon species having a high specific surface area (BET) with silicon, tin and/or silicon/tin nanoparticies embedded in them are formed as will be described further below.
  • BET specific surface area
  • the conversion of the polymeric starting material to carbon takes place within the scope of this process step, i.e., in other words, the polymeric starting material containing carbon undergoes carbonization.
  • the carbonization is performed under at least essentially inert conditions, in particular in the absence of oxygen, preferably under an inert gas atmosphere. In this way excessive turnoff is prevented on the one hand while on the other hand unwanted oxidation of the silicon to silicon dioxide and/or oxidation of the tin to tin oxide is/are prevented.
  • the carbonization is usually performed at temperatures in the range of 300 to 2000° C. in particular 600 to 1200° C., preferably 700 to 1000° C., with periods of time of 0.1 to 20 hours, preferably 0.5 to 10 hours, especially preferably 1 to 5 hours being customary in particular.
  • the carbonization should not be followed by any more extensive activation step according to the invention such as would otherwise be customary in the production of activated carbon because this would lead to the unwanted oxidation of the silicon and/or tin, as described above.
  • the silicon- and/or tin-containing carbon material it is possible to provide for the addition of graphite and/or at least one conductivity-improving substance, in particular conductive carbon black during the course of the process.
  • the graphite and/or the conductivity-improving substance, in particular conductive carbon black may be added to the monomers to be polymerized and/or to the polymers. Alternatively the graphite and/or the conductivity-improving substance may also be added to the finished carbon material after carbonization.
  • the subject matter of the present invention is the electrically conductive porous carbon materials containing silicon and/or tin according to the method according to the invention.
  • the subject matter of the present invention is an electrically conductive porous carbon material containing silicon and/or tin, which is suitable in particular for the production of an anode material, preferably for lithium-ion batteries, such that the carbon material containing silicon and/or tin contains silicon nanoparticies and/or tin nanoparticles and/or silicon/tin nanoparticles intercalated into a porous carbon matrix.
  • anode material preferably for lithium-ion batteries
  • the carbon material according to the invention is characterized by a high porosity, which permits a problem-free and reversible intercalation of lithium ions because the silicon, tin and/or silicon/tin nanoparticles are readily accessible due to the porosity and furthermore this allows a problem-free volume expansion (“breathing of the silicon and/or tin”).
  • the carbon materials according to the invention in particular are characterized by a porosity, determined as the total pore volume according to Gurvich, in the range of 0.01 to 4 m 3 /g, in particular 0.1 to 3.5 m 3 /g, preferably 0.2 to 3 m 3 /g, especially preferably 0.3 to 2.0 m 3 /g.
  • the silicon- and/or tin-containing carbon material according to the invention has a porosity such that at least 10 vol % in particular at least 15 vol %, preferably at least 20 vol % of the total volume of the carbon material is formed by pores and/or is embodied in a porous form.
  • the carbon materials according to the invention are characterized by a high internal surface area (BET).
  • BET high internal surface area
  • the carbon materials according to the invention have a BET surface area of 50 to 2000 m 2 /g in particular 100 to 1750 m 2 /g preferably 200 to 1500 m 2 /g.
  • silicon and/or tin and/or nanoparticle content i.e., silicon, tin and/or silicon/tin nanoparticles
  • silicon, tin and/or silicon/tin nanoparticles may vary in wide ranges.
  • the molar silicon content and/or tin content (i.e., the molar silicon, tin and/or silicon/tin nanoparticle content) in the carbon materials according to the invention may vary in the range of 5 to 90 mol %, in particular 10 to 80 mol %, preferably 20 to 70 mol %, based on the carbon material.
  • volume-based silicon and/or tin content i.e., the volume-based silicon, tin and/or silicon/tin nanoparticle content
  • the volume-based silicon and/or tin content in the carbon material according to the invention varies in the range of 1 to 60 vol % in particular 2 to 50 vol %, preferably 5 to 40 vol % based on the carbon material.
  • the mass-based silicon and/or tin content (i.e., the mass-based silicon, tin and/or silicon/tin nanoparticle content) in the carbon material according to the invention is in the range of 1 to 70 wt %, in particular 2 to 60 wt %, preferably 5 to 50 wt %, based on the carbon material.
  • the carbon material according to the invention may also contain graphite.
  • the carbon material preferably contains graphite in molar amounts of 1 to 50 mol %, preferably 5 to 40 mol %, based on the carbon material in this embodiment, the graphite may be present in mass-based amounts of 0.001 to 50 wt %, in particular 0.01 to 45 wt %, preferably 0.1 to 40 wt %, especially preferably 1 to 40 wt %, based on the carbon material.
  • the BET surface area of the graphite used may vary in the range of 1 to 75 m 2 /g especially 2 to 50 m 2 /g, preferably 5 to 30 m 2 /g, especially preferably 10 to 20 m 2 /g.
  • Those skilled in the art are familiar with graphites that may be used to improve the electrical conductivity. These products are available commercially.
  • the carbon material according to the invention may optionally contain at least one conductivity-improving agent, in particular a conductive carbon black.
  • the conductivity-improving agent in particular conductive carbon black may be present in molar amounts of 1 to 20 mol preferably 3 to 10 mol %, based on the carbon material.
  • the conductivity-improving agent, especially the conductive carbon black is usually present in mass-based amounts of 0.001 to 20 wt %, especially 0.01 to 15 wt %, preferably 0.1 to 10 wt %, based on the carbon material.
  • conductivity-improving agents that may be used for this purpose, in particular conductive carbon blacks, which are also available commercially.
  • Conductivity-improving agents in particular conductive carbon blacks having average particle sizes (D 50 ) in the range of 1 to 1.00 nm, in particular 20 to 60 nm, preferably 30 to 50 nm are advantageously used.
  • Conductivity-improving agents suitable for use according to the invention, in particular conductive carbon blacks have BET surface areas in the range of 10 to 200 m 2 /g especially 50 to 80 m 2 /g, preferably 55 to 70 m 2 /g.
  • the carbon material according to the invention is characterized by a good electrical conductivity.
  • the electrical conductivity of the carbon material according to the invention is usually in the range of 10 0 to 10 6 S/m especially 5 ⁇ 10 0 to 10 5 S/m.
  • the conductivity of the carbon material according to the invention especially amounts to at least 10 0 S/m especially at least 10 3 S/m, preferably at least 10 4 S/m.
  • the present invention relates to the use of the carbon material according to the invention as an anode material especially for lithium-ion batteries and/or for producing an anode material especially for lithium-ion batteries.
  • Another subject matter of the present invention is an anode material which contains the carbon material according to the present invention as described above.
  • the anode material according to the present invention is made exclusively of the carbon material according to the invention. This is the case in particular when the carbon material according to the invention is processed into molded bodies suitable for use as anodes and also has a sufficient mechanical stability.
  • the carbon material according to the invention may be processed together with other components in particular graphite and/or conductivity-improving agents in particular conductive carbon black and/or binders to form an anode material according to the present invention, which is suitable in particular as an anode material for lithium-ion batteries.
  • An anode material according to the present invention which is suitable in this context may contain in particular
  • binders in particular organic binders, suitable for use according to the invention, as such.
  • the binders may be any binders that permanently bind and/or hold together the aforementioned components.
  • Preferred binders include polymeric binders preferably polyvinylidene fluoride, polytetrafluoroethylene or polyolefins, especially preferably thermoplastic elastomers in particular ethylene-propylene-diene terpolymers.
  • Gelatin or modified cellulose may also be used as binders.
  • the anode material according to the invention is characterized by a good electrical conductivity which is in particular in the range of 10 1 to 10 5 S/m especially 5 ⁇ 10 1 to 10 4 S/m.
  • the anode material according to the invention is characterized by a conductivity of at least 10 1 S/m especially at least 10 2 S/m preferably at least 10 3 S/m.
  • the subject matter of the present invention is a battery especially a lithium-ion battery preferably in the form of an accumulator, comprising an anode material according to the present invention as defined above and/or a carbon material according to the present invention as defined above.
  • porous silicon- and/or tin-containing products and/or materials which are suitable as the anode material for lithium-ion batteries, in particular are made available.
  • the subject matter of the invention is thus a porous to highly porous material for use as anode material in lithium-ion batteries.
  • Crystalline silicon nanoparticles, silicon/tin nanocomposite particles, nanoparticies based on silicon/tin alloys or tin nanoparticles produced by gas-phase synthesis or the like, for example, for the aforementioned purpose may typically be dispersed homogeneously in a monomer with subsequent polymerization or a polymer and then polymerized.
  • Crystalline nanoparticles of silicon and/or tin for the material according to the invention may first be dispersed homogeneously in a monomer which is then polymerized in situ in the presence of the silicon and/or tin or alternatively may be dispersed homogeneously in a polymer (organic). As explained previously, in the case of the monomer, the latter is then polymerized.
  • the polymers are processed further, for example, to molded articles such as spheres, wafers, blocks or more complex structures and then pyrolyzed thus yielding a carbon species with a large internal surface area (BET) (e.g., typically a few 100 m 2 /g to 2000 m 2 /g) and silicon, in and/or silicon/tin nanoparticles embedded therein.
  • BET internal surface area
  • silicon nanoparticles aggregated (so-called “hard agglomerates”) and unaggregated (so-called “soft agglomerates”) silicon with an average crystallite size between 1 and 100 nm is especially suitable. Silicon with an average crystallite size between 5 and 50 nm is most especially suitable.
  • the average crystallite size can determined, for example, from histograms with transmission electron micrographs and/or from x-ray diffractograms as well as—in the case of the unaggregated powder—from the BET surface area.
  • the silicon, tin and/or silicon/tin nanoparticles functionalized in this way can be bound by dispersion of these particles in a liquid/viscous monomer or polymer, for example, by stirring, kneading, milling in particular in ball mills, ultrasound, extrusion, etc.
  • Monomers and/or polymers that may be especially suitable for use according to the invention include organic compounds which do not contain any chemically bound oxygen in particular (poly) vinyl chloride, (poly)styrene, (poly)tetrafluoroethylene, (poly)ethylene and (poly) propylene; (poly) styrene is especially suitable, preferably with divinylbenzene as the crosslinking agent.
  • the silicon and/or tin and/or silicon/tin powder may be nominally undoped or may have a p- or n-type doping of up to 10 21 /cm 3 .
  • Elements of Main Groups 3 and 5 are preferred (new nomenclature: group 13 and 15) of the periodic system of elements as well as elements from the iron group and especially preferably boron, aluminum, phosphorus and/or iron.
  • Another possibility for producing the actual anodes starting from the emitted anode material is to also add graphite and/or conductive carbon black to the dispersion of monomer and/or polymer and silicon, tin and/or silicon/tin nanoparticles in order to improve the uptake capacity for lithium and to improve the electrical conductivity.
  • the addition of graphite may typically amount to 1 to 50 mol %, preferably 5 to 40 mol %, based on the material according to the invention.
  • the addition of conductive carbon black may amount to typically 1 to 20 mol %, preferably 3 to 10 mol %, based on the material according to the invention.
  • the silicon and/or tin content in the material according to the invention may typically be varied in a wide range.
  • a composition may contain 5 to 90 mol %, preferably 20 to 70 mol % silicon and/or tin based on the material according to the invention.
  • the silicon powder functionalized in this way is dispersed in 1.00 mL styrene with the help of an ultrasound generator, and then 5 g divinylbenzene and 5 g dibenzoyl peroxide are added one after the other to the dispersion.
  • the suspension is heated in a boiling water bath for 30 minutes while stirring, poured into a mold and cooled.
  • the filter residue is transferred to a tubular oven and pyrolyzed at 750° C. for 3 hours under nitrogen.
  • the resulting material is then processed together with a binder and optionally together with graphite and/or conductive carbon blacks to form anodes for lithium-ion batteries.
  • Tin-based and/or silicon/tin-based anode materials are prepared by a comparable method, using as starting materials surface-oxidized tin composite and/or silicon/tin, produced from microwave synthesis as the starting materials instead of silicon, in deviation from the preceding exemplary embodiment.

Abstract

The invention relates to a process for producing an electrically conductive, porous, silicon- and/or tin-containing carbon material which is suitable in particular for the production of an anode material, preferably for lithium ion batteries; in a first step of the process, preferably crystalline silicon nanoparticles and/or tin nanoparticles and/or silicon/tin nanoparticles are introduced into a matrix based on at least one organic polymer, being more particular dispersed therein, and subsequently, in a second step of the process, the resultant polymer matrix containing the silicon, tin and/or silicon/tin nanoparticles is carbonized to form carbon.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS
This application is a National Stage filing of International Application PCT/EP 2009/005110, filed Jul. 14, 2009, entitled “INTERCALATION OF SILICON AND/OR TIN INTO POROUS CARBON SUBSTRATES” claiming priority to German Applications No. DE 10 2008 033 097.3 filed Jul. 15, 2008, and DE 10 2008 045 231.9 filed Aug. 30, 2008. The subject application claims priority to PCT/EP 2009/005110, and to German Applications No. DE 10 2008 033 097.3, and DE 10 2008 045 231.9 and incorporates all by reference herein, in their entirety.
BACKGROUND OF THE INVENTION
The present invention, relates to the field of lithium-ion battery technology, in particular anode materials suitable in this regard and their production.
The present invention relates in particular to a method for manufacturing an electrically conductive, porous, silicon- and/or tin-containing carbon material as well as the carbon material itself produced in this way and its use in particular for production of anode materials, preferably for lithium-ion batteries.
In addition, the present invention relates to anode materials containing the carbon material according to the invention and/or using the carbon material according to the invention as well as batteries, in particular lithium-ion batteries comprising these anode materials.
Lithium-ion batteries are characterized by very high energy densities. They are thermally stable, supply a constant voltage over the duration of the discharge time and do not have a so-called memory effect. Such batteries are known in the prior art in the form of traditional batteries for a single use as well as in the form of rechargeable batteries.
Lithium-ion batteries generate the electromotive force by displacement of lithium ions. In the charging process, positively charged lithium ions migrate through the electrolyte from a cathode between the graphite planes of an anode, while the charging current supplies the electrons over the external circuit, such that the ions form an intercalation compound of the LixnC type with graphite. On discharging, the lithium ions migrate back and the electrons can flow over the external circuit to the cathode.
The term. “intercalation” in the sense of the present invention refers to the intercalation of a mobile-guest species into a host lattice without destroying the structural principle of the host substance and/or the host lattice. The host lattices have layered structures, tubular structures or cage structures, for example, in which the guest substance can be intercalated in a one-, two- or three-dimensional arrangement, often with volume expansion. The intercalation of ions is associated with oxidation or reduction of the host lattice. In electrochemical intercalation, an electronically conductive host as the electrode is anodically or cathodically polarized in the electrolyte, so that anions and/or cations, optionally solvated, move from the electrolyte into the host lattice. This electron/ion transfer reaction results in a mixed conductor, which usually has a better electronic conductivity than the starting material. Electrochemical intercalation reactions are usually reversible and the mobility of the guest ions is high, in particular in host lattices having a layered structure. Intercalation performed in this way includes three basic steps: diffusion or migration of ions, which are usually solvated, to the electrochemical double layer of the host lattice, possible desolvation and subsequent transfer of the ions into free lattice sites near the surface region of the host, and finally, diffusion of the ions into the interior of the lattice.
The concept of intercalation electrodes for electro-chemical current sources has been attracting great interest again, at the latest since the rapid development of rechargeable lithium cells. Intercalation electrodes have been investigated widely since the 1970s for applications in organic and aqueous electrolyte solutions. In other galvanic elements that have already been known of for a long time, e.g., the Zn/MnO2 element and the lead battery, reduction of the cathodic oxides takes place by way of the intercalation of a proton in MnO2 and/or PbO2.
The actual breakthrough in rechargeable lithium batteries was achieved for the first time with the market introduction of a cell which completely omits metallic lithium as an anode material namely the lithium ion cell. Instead of metallic lithium, lithium ion intercalation compounds, for example, lamellar carbon, transition metal oxides or metals forming alloys with lithium are used as the negative active compounds which can reversibly take up and release lithium ions. The positive lithium ion charges are neutralized by electron uptake or release by the host material. In comparison with metallic lithium, the theoretical values for the specific charge in use of an inactive host material are usually much lower.
Since the lithium activity in the intercalation compounds—frequently also called insertion or intercalation compounds—is lower than that of the metallic lithium, i.e., lower than 1, so the electrode potential is also shifted toward less negative values depending on the charge state. However, instead of lithium atoms, lithium ions which are much smaller are used in lithium ion intercalation compounds.
The prerequisite for intercalation of lithium ions in a host lattice material is that the host lattice matrix must be able to allow the uptake of host ions not only sterically but also electronically, i.e., must have a corresponding structure of the energy bands.
The active material of the anode of a conventional lithium-ion battery is made of graphite for example. The cathode contains, for example, lithium metal oxides in a layered structured such as lithium cobalt oxide, lithium nickel oxide or the spinel LiMn2O4. Lithium-ion batteries must be completely anhydrous because otherwise the water can react with the conductive salt (e.g., LiPF6) to form hydrofluoric acid (HF). Therefore a mixture of anhydrous aprotic solvents is usually chosen.
As mentioned previously, lithium-ion batteries usually do not have the so-called memory effect and also have an extremely low spontaneous discharge or none at all. Lithium-ion batteries are able to supply power to portable electronic devices having a high power demand when these devices would be too heavy or too large for traditional lead batteries, for example, cellular telephones, digital cameras, camcorders or laptops as well as electric vehicles and hybrid vehicles. In the model building sector and in electric power tools, they have already become well established. The usable lifetime of lithium-ion batteries is several years, for example, although that depends greatly on the use and storage conditions.
Because of the positive properties of lithium-ion batteries including lithium ion accumulators as described previously, there has been no lack of attempts in the prior art to develop the technology in this respect further.
It is known from the prior art that silicon, especially in particulate form, may be mixed into a carbon or graphite matrix or otherwise introduced, for example, by gas phase deposition or the like (in this regard, cf. also the documents WO 2005/096414 A2, DE 10 2005 011 940 A1, DE 103 53 996 A1, DE 103 53 995 A1 and DE 10 2006 010 862 A1, for example). It is fundamentally known to those skilled in the art that within the context of lithium-ion batteries, silicon is mechanically degraded and amorphized due to the volume contraction and expansion which occur during charging and discharge processes and ultimately the silicon is no longer available for storage of lithium due to obviously inferior electrical contacting and destruction. The increasingly inferior electrical contacting is counteracted by the intercalation of silicon in a carbon or graphite matrix.
N. Dimovet et al., Journal of Power Sources, 136 (2004, pages 108 ff., describe a method for mechanical mixing of silicon particles approximately 1 μm in size with natural and synthetic graphite.
Kim et al., Journal of Power Sources, 136 (2004), pages 145 ff., describe a method for mechanical mixing of silicon nanoparticies with polystyrene.
Kwon et al., Chem. Commun., 2008, pages 1109 ff., describe a method for coating Si70Sn30 nanoalloys with carbon.
WO 2005/096414 A2 describes an electrode material which is produced by mechanical mixing of particles, carbon black and graphite.
An overview of the prior art can be found, for example, in Kasavajjula et al., Journal of Power Sources, 163 (2007), pages 1003 ff.
However, all the methods known in the prior art discuss only the electrical properties or capacitances of the materials.
The mechanical properties of the powder, in particular those with regard to the availability of the expansion volume for silicon are not discussed at all or are discussed only peripherally.
A number of disadvantages are associated with the silicon-containing materials proposed as the anode materials for lithium-ion battery in the prior art: a plurality of silicon-containing anode materials proposed in the prior art tend to cause mechanical degradation and amorphization so that ultimately lithium can no longer be stored due to a lack of electrical contacting. Because of the often inadequate porosity of the matrix and host structure, this matrix and/or host structure often suffers irreversible damage due to the volume contraction that occurs in the charging operation. The materials known in the prior art often do not have adequate mechanical properties, in particular do not have the corresponding strengths.
BRIEF SUMMARY OF THE INVENTION
The object of the present invention is therefore to provide a material suitable as the anode material for lithium-ion batteries and to provide a corresponding method for producing same, such that the disadvantages of the prior art described above are avoided at least partially or they should at least be diminished.
To solve the problem described above the present invention proposes a method described herein. The subject matter of the present invention—according to a first aspect of the present invention—is thus a method according to claim 1. Additional advantageous embodiments of this aspect of the invention are the subject matter of the subsidiary claims in this regard.
Another subject matter of the present invention—according to a second aspect of the present invention—is the materials and/or products obtainable by the method according to the invention, as described herein; additional embodiments of this aspect of the invention are similarly described.
In turn another subject matter of the present invention—according to a third aspect of the present invention—is the use of the materials and/or products as further described herein and obtainable by the method according to the invention.
In addition, another subject matter of the present invention—according to a fourth aspect of the present invention—is an anode material described herein; additional advantageous embodiments of this aspect of the invention are similarly described.
Finally another subject matter of the present invention—according to a fifth aspect of the present invention—is a battery in particular a lithium-ion battery described herein.
It is self-evident that, to avoid repetition, statements made below concerning only one aspect according of the invention also apply to the other aspects of the invention accordingly, even if this is not stated or pointed out explicitly.
It is likewise self-evident that those skilled in the art may deviate from the specific (numerical) values and ranges given, based on the application or in the individual case, without going beyond the scope of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The subject matter of the present invention—according to a first aspect of the present invention—is thus a method for producing an electrically conductive, porous, silicon- and/or tin-containing carbon material which is suitable in particular for producing an anode material, preferably for lithium-ion batteries, such that in a first process step silicon nanoparticles and/or tin nanoparticles and/or silicon/tin nanoparticles are introduced into a matrix based on at least one organic polymer, in particular being dispersed therein, and subsequently in a second process step the polymer matrix obtained in this way and containing the silicon nanoparticles and/or tin nanoparticles and/or silicon/tin nanoparticles is carbonized to carbon. In other words, the subject matter of the present invention according to this aspect of the invention relates a method for intercalating silicon and tin into porous carbon substrates by the aforementioned process steps. The silicon, tin and/or silicon/tin nanoparticles are preferably introduced and/or intercalated and/or dispersed homogeneously and/or in a uniform distribution in the organic polymer matrix.
A number of advantages are associated with the method according to the invention and the materials and/or products produced with this method, but only a few advantages will be pointed out below.
By intercalating silicon and/or tin into a porous matrix based on carbon, this effectively counteracts the mechanical degradation and amorphization of the crystalline silicon and/or tin which occurs due to volume contraction and expansion during the charging and discharging processes when used as an anode material in particular for lithium-ion batteries, so that the electrical conductivity in particular the ability to store lithium ions, is preserved.
By embedding the silicon and/or tin in a porous carbon matrix, a deterioration of the electrical contacting in particular is also counteracted. The use of nanoscale silicon and/or silicon also makes it possible to effectively counteract destruction of the matrix which occurs due to changes in volume because nanoscale material is much more tolerant in this regard. Embedding nanoscale silicon and/or tin in a porous to highly porous but nevertheless mechanically stable host matrix of carbon ensures on the one hand a good electrical contact between silicon and/or tin and carbon, but on the other hand also allows the silicon and/or tin to “breathe” within this matrix (i.e., allowing free volume expansion due to intercalation of lithium ions in the charging process) because sufficient volume is available due to the high porosity without the host structure being damaged.
The materials according to the invention also have excellent mechanical properties in particular with regard to the availability of the expansion volume for the silicon and/or tin but also with regard to the mechanical strength for use as an anode material.
On the one hand, a system that is especially stable mechanically and permits adequate volume expansion while on the other hand also having excellent electrical conductivity due to the excellent electrical contact between silicon and/or tin and carbon is made available by intercalation of the silicon, tin and/or silicon/tin nanoparticies in the polymer matrix, in particular by means of in situ polymerization in the presence of the silicon, tin and/or silicon/tin nanoparticies and subsequent carbonization (also referred to by the synonyms “coking,” “pyrolysis,” “burn-off” or the like).
For the reasons given above, the products obtainable according to the invention are suitable in particular for use as silicon- and/or tin-containing anode materials, preferably for lithium-ion batteries, including accumulators, because despite the volume contraction and expansion occurring during the charging and discharging processes, they do not have a tendency to any mentionable mechanical degradation and amorphization of the silicon and/or tin and/or do not have any such tendency at all and an excellent electrical contacting associated with an excellent ability to store lithium ions is preserved. Due to the adequate porosity of the matrix structure and/or host structure, there is also no irreversible damage to this matrix and/or host structure due to the volume contraction occurring in the charging process. The silicon- and/or tin-containing materials obtainable according to the invention have excellent mechanical properties, in particular appropriate strengths with at the same time good availability of the required expansion volume for the silicon and/or tin.
According to the invention it is thus surprisingly possible to produce materials having such mechanical properties that they directly supply the form of ready-to-use electrodes so that in the production of anodes, it is possible to completely omit the addition of a binder, in particular an organic binder (in general a few wt %) to produce mechanically strong electrodes.
In the method according to the invention as described above, the process management according to the invention leads to an electrically conductive porous carbon material with silicon, tin and/or silicon/tin nanoparticies intercalated into them, i.e., the result is thus porous carbon substrates with nanoparticulate silicon and/or tin intercalated therein.
With regard to the nanoparticies used (i.e., silicon, tin and/or silicon/tin nanoparticles), these are in particular particles having an average particle size (D50) in particular an average crystallite size (D50) in the range of 1 to 1000 nm in particular 2 to 500 nm, preferably 2 to 250 nm, especially preferably 5 to 100 nm, most especially preferably 5 to 50 nm.
Nanoparticles having an average crystallite size between 1 and 100 nm are especially suitable. Nanoparticles having an average crystallite size between 5 and 50 nm are suitable in particular.
In the case of silicon nanoparticles, aggregated silicon (so-called “hard agglomerates”) is especially suitable, as is also unaggregated silicon (so-called “soft agglomerates”) each with an average crystallite size between 1 and 100 nm. In this case silicon with an average crystallite size between 5 and 50 nm is especially suitable.
The aforementioned average particle sizes and/or crystallite sizes can be determined, for example, from histograms of transmission electron micrographs or from x-ray diffractograms as well as—for example, in the case of unaggregated silicon—from the BET surface area.
Preferably crystalline silicon, tin and/or silicon/tin nanoparticles produced by gas-phase synthesis, microwave plasma synthesis or the like can typically be used for the purposes according to the invention, for example. Suitable silicon, tin and/or silicon/tin nanoparticles, in particular those that are crystalline, can be obtained, for example, in a microwave plasma in the case of silicon nanoparticles starting from silane or in the case of tin nanoparticles starting from stannan or finally in the case of Si/Sn nanoparticles to be used according to the invention, starting from silane/stannan mixtures or silane/tin tetrachloride mixtures. Those skilled in the art are familiar with this as such so no further details need be given at this point.
As explained above, the silicon, tin and/or silicon/tin nanoparticles to be used according to the invention are usually embodied in a crystalline form. The degree of crystallinity of the silicon, tin and/or silicon/tin nanoparticles used is advantageously at least 70%, in particular at least 80%, preferably at least 90%, especially preferably at least 95% and most especially preferably the silicon, tin and silicon/tin nanoparticles used are embodied in a completely crystalline form.
Silicon, tin and silicon/tin nanoparticles suitable for use according to the invention usually have a PET surface area of 1 to 2000 m2/g in particular 10 to 1500 m2/g, preferably 25 to 1000 m2/g and especially preferably 50 to 600 m2/g. All the BET values determined and/or mentioned within the scope of the present invention are determined according to ISO 9277 (1995) which replaces DIN 66131.
The silicon nanoparticles used according to the invention may in particular consist of pure silicon but they may also be provided with at least one doping element as described below. In the case of the tin nanoparticles used according to the invention, they may be made or pure tin in particular, but may also be provided with at least one doping element as described below. In the case of the silicon/tin nanoparticles used according to the invention, they may consist in particular of silicon/tin mixtures in any mixing ratio, in particular based on silicon/tin composites or silicon/tin alloys, but the silicon/tin nanoparticles may optionally also be provided with at least doping element, as described below. Nanoparticles based on silicon/tin composites or silicon/tin alloys are preferably used according to the invention. Tin has the advantage of having a good electrical conductivity.
In addition, it is possible for the silicon, tin and silicon/tin nanoparticies that are used, in particular crystalline nanoparticles to be doped and/or to contain at least one doping element. The silicon, tin and/or silicon/tin nanoparticies according to the invention may in particular have a p-type and/or n-type doping, preferably of up to 1021/cm3, where the doping elements may be selected from Main Groups 3 to 5 of the periodic system of elements (corresponding to groups 13 to 15 of the periodic system of elements according to the new nomenclature) and from elements of the iron group, in particular from the group of boron, aluminum, phosphorus and/or iron as well as mixtures thereof.
It is possible in particular to provide for the silicon, tin and/or silicon/tin nanoparticies to be doped and/or to contain at least one doping element, where this doping element may be selected in particular from the group of phosphorus, arsenic, antimony, boron, aluminum, gallium and/or indium.
The amount of silicon, tin and/or silicon/tin nanoparticles used may vary in wide ranges.
The silicon, tin and/or silicon/tin nanoparticies are generally used within the scope of the method according to the invention in amounts such that the molar silicon and/or tin content (i.e., the molar silicon, tin and/or silicon/tin nanoparticle content) in the electrically conductive, porous, silicon- and/or tin-containing carbon material amounts to 5 to 90 mol %, in particular 10 to 80 mol %, preferably 20 to 70 mol %, based on the electrically conductive, porous, silicon- and/or tin-containing carbon material.
In an advantageous manner according to the invention, the silicon, tin and/or silicon/tin nanoparticles are used in amounts within the scope of the method according to the invention, such that the silicon and/or tin content based on volume (i.e., the volume-based silicon, tin, and/or silicon/tin nanoparticle content) in the electrically conductive, porous, silicon- and/or tin-containing carbon material amounts to 1 to 60 vol %, in particular 2 to 50 vol %, preferably to 4.0 vol %, based on the electrically conductive, porous, silicon- and/or tin-containing material.
The silicon, tin and/or silicon/tin nanoparticies are typically used in such amounts within the scope of the method according to the invention that the silicon and/or tin content based on mass (i.e., the mass-based silicon, tin and/or silicon/tin nanoparticle content) in the electrically conductive, porous, silicon- and/or tin-containing carbon material is 1 to 70 wt %, in particular 2 to 60 wt %, preferably 5 to 50 wt %, based on the electrically conductive, porous, silicon- and/or tin-containing carbon material.
The silicon, tin and/or silicon/tin nanoparticles are advantageously subjected to a surface modification and/or surface functionalization, preferably a hydrophobization prior to being introduced into the organic polymer, in particular before being dispersed in the organic polymer. In particular the surface modification and/or surface functionalization may be performed by alkylsilyl group functionalization, preferably by methylsilyl group functionalization (e.g., trimethylsilyl group functionalization). The functionalization of the surface of nanoparticles the in particular for the purposes of hydrophobization is advantageous to disperse the silicon, in and/or silicon/tin nanoparticles in the polymer and/or the starting monomers in this regard, in particular homogeneously. For functionalization, reactive silanes may be used in particular. Chlorosilanes and hexamethyldisilazane are especially preferred, chlorosilanes of the general formula. SiClxR4-x where x=1 to 3 are especially preferred, where the R radical denotes an organic radical, preferably an alkyl radical, preferably having the general formula CnH(2n+1), especially preferably where n=1 to 6.
According to an especially preferred embodiment, the organic polymer is created in situ in the presence of the silicon, tin and/or silicon/tin nanoparticies. To this end the silicon, tin and/or silicon/tin nanoparticies which have preferably first been surface modified and/or surface functionalized in particular hydrophobized, are dispersed in the corresponding organic monomers and/or solutions or dispersions thereof and then the organic monomers are subsequently polymerized in the presence of the silicon, tin and/or silicon/tin nanoparticles to form the respective organic polymers. The result is an organic polymer matrix in which the silicon, tin and/or silicon/tin nanoparticles are intercalated and/or embedded, preferably in a homogeneous and/or uniform distribution such that this polymer matrix is then subsequently carbonized and/or pyrolyzed as will be described in detail below.
In the previously described special embodiment according to which organic monomers are used which are then polymerized in situ in the presence of the silicon, tin and/or silicon/tin nanoparticles in particular monomers which do not contain any chemically bound oxygen are used. Organic, monomers preferred according to this invention are selected in particular from the group of vinyl chloride, styrene, tetrafluoroethylene, ethylene and/or polypropylene, preferably styrene, especially preferably styrene together with divinylbenzene (in the latter case, divinylbenzene-crosslinked polystyrene is formed after polymerization, as will be described below).
Within the scope of the method according to the present invention, organic polymers which do not contain any chemically bound oxygen are preferably used as the organic polymers which form the matrix for the silicon, tin and/or silicon/tin nanoparticles to be intercalated therein. Chemically bound oxygen is capable of oxidizing a portion of the silicon, tin and/or silicon/tin nanoparticles to silicon dioxide and/or tin oxide in the subsequent carbonization, but these oxides would then be useless for the application as anode material, in particular for lithium-ion batteries. The organic polymers which form the matrix for the silicon, tin and/or silicon/tin nanoparticles to be intercalated therein are selected in a manner preferred according to the invention from the group of polyvinyl, chloride, polyacrylonitrile, polystyrene, polytetrafluoroethylene, polyethylene and/or polypropylene, preferably polystyrene. Divinylbenzene-cross linked polystyrene is especially preferred, in particular with a divinylbenzene content of 0.1 to 20 wt %, preferably 1 to 10 wt %, based on the organic polymer.
It is preferable-according to the invention if the organic monomers and/or the organic polymers are present in sulfonated form and/or contain sulfonic acid groups. The sulfonic acid groups are usually not introduced until after production of the polymer and/or before the process step of carbonization, namely by sulfonation in a known manner. Sulfonic acid groups form free radicals in the subsequent carbonization, leading to the crosslinking which responsible for the good carbon yield in the context of the pyrolysis process. Instead of sulfonic acid groups, fundamentally other chemically suitable groups may also be used, for example, isocyanate groups.
With regard to the intercalation and/or dispersion of the silicon, tin and/or silicon/tin nanoparticies in the organic monomers and/or polymers, this may be performed by those skilled in the art in the usual manner, for example, by stirring, kneading, milling using a ball mill, ultrasonic treatment, extrusion, etc.
According to a special embodiment of the present invention, the polymers containing the silicon, tin and/or silicon/tin nanoparticles may be subjected to a shaping process before the process step of carbonization. For example, the polymers containing silicon, tin and/or silicon/tin nanoparticles may be processed further to molded articles such as spheres, disks, blocks, more complex structures or the like which are subsequently carbonized and/or pyrolyzed so that carbon species having a high specific surface area (BET) with silicon, tin and/or silicon/tin nanoparticies embedded in them are formed as will be described further below.
With regard to the process step of carbonization, which is also referred to by such synonyms as “pyrolysis,” “low-temperature carbonization” or the like, the conversion of the polymeric starting material to carbon takes place within the scope of this process step, i.e., in other words, the polymeric starting material containing carbon undergoes carbonization. In carbonization or low-temperature carbonization of the aforementioned polymers, which contain functional chemical groups that form free radicals and thus leading to crosslinking in their thermal decomposition, in particular sulfonic acid groups, the functional chemical groups, in particular the sulfonic acid groups, are destroyed—splitting off volatile component such as SO2 in particular—and free radicals are formed which cause a strong crosslinking without forming any mentionable pyrolysis residue (=carbon).
In general, the carbonization is performed under at least essentially inert conditions, in particular in the absence of oxygen, preferably under an inert gas atmosphere. In this way excessive turnoff is prevented on the one hand while on the other hand unwanted oxidation of the silicon to silicon dioxide and/or oxidation of the tin to tin oxide is/are prevented.
The carbonization is usually performed at temperatures in the range of 300 to 2000° C. in particular 600 to 1200° C., preferably 700 to 1000° C., with periods of time of 0.1 to 20 hours, preferably 0.5 to 10 hours, especially preferably 1 to 5 hours being customary in particular.
The carbonization should not be followed by any more extensive activation step according to the invention such as would otherwise be customary in the production of activated carbon because this would lead to the unwanted oxidation of the silicon and/or tin, as described above.
To further improve the electrical conductivity of the silicon- and/or tin-containing carbon material according to the present invention, it is possible to provide for the addition of graphite and/or at least one conductivity-improving substance, in particular conductive carbon black during the course of the process. The graphite and/or the conductivity-improving substance, in particular conductive carbon black, may be added to the monomers to be polymerized and/or to the polymers. Alternatively the graphite and/or the conductivity-improving substance may also be added to the finished carbon material after carbonization. With respect to a more extensive characterization of the graphites and/or conductivity-improving substances to be added in this quantities to be used in this regard, reference can be made to the following discussion regarding the silicon- and/or tin-containing carbon materials according to the present invention, which are applicable accordingly with respect to the process according to the invention.
The subject matter of the present invention—according to a second aspect or the present invention—is the electrically conductive porous carbon materials containing silicon and/or tin according to the method according to the invention.
In other words, the subject matter of the present invention according to this aspect of the invention is an electrically conductive porous carbon material containing silicon and/or tin, which is suitable in particular for the production of an anode material, preferably for lithium-ion batteries, such that the carbon material containing silicon and/or tin contains silicon nanoparticies and/or tin nanoparticles and/or silicon/tin nanoparticles intercalated into a porous carbon matrix. For more extensive details concerning this aspect of the invention, reference may be made to the preceding discussion of the method according to the invention which also applies here accordingly to the carbon material according to the invention.
As explained above, the carbon material according to the invention is characterized by a high porosity, which permits a problem-free and reversible intercalation of lithium ions because the silicon, tin and/or silicon/tin nanoparticles are readily accessible due to the porosity and furthermore this allows a problem-free volume expansion (“breathing of the silicon and/or tin”).
The carbon materials according to the invention in particular are characterized by a porosity, determined as the total pore volume according to Gurvich, in the range of 0.01 to 4 m3/g, in particular 0.1 to 3.5 m3/g, preferably 0.2 to 3 m3/g, especially preferably 0.3 to 2.0 m3/g.
It is especially advantageous if the silicon- and/or tin-containing carbon material according to the invention has a porosity such that at least 10 vol % in particular at least 15 vol %, preferably at least 20 vol % of the total volume of the carbon material is formed by pores and/or is embodied in a porous form. Preferably 10 to 80 vol % in particular 15 to 75 vol %, preferably 20 to 60 vol % of the total volume of the carbon material is formed by pores.
In addition, the carbon materials according to the invention are characterized by a high internal surface area (BET). In particular the carbon materials according to the invention have a BET surface area of 50 to 2000 m2/g in particular 100 to 1750 m2/g preferably 200 to 1500 m2/g.
As explained previously the silicon and/or tin and/or nanoparticle content (i.e., silicon, tin and/or silicon/tin nanoparticles) in the carbon materials according to the invention may vary in wide ranges.
For example, the molar silicon content and/or tin content (i.e., the molar silicon, tin and/or silicon/tin nanoparticle content) in the carbon materials according to the invention may vary in the range of 5 to 90 mol %, in particular 10 to 80 mol %, preferably 20 to 70 mol %, based on the carbon material.
In addition, the volume-based silicon and/or tin content (i.e., the volume-based silicon, tin and/or silicon/tin nanoparticle content) in the carbon material according to the invention varies in the range of 1 to 60 vol % in particular 2 to 50 vol %, preferably 5 to 40 vol % based on the carbon material.
Finally, the mass-based silicon and/or tin content (i.e., the mass-based silicon, tin and/or silicon/tin nanoparticle content) in the carbon material according to the invention is in the range of 1 to 70 wt %, in particular 2 to 60 wt %, preferably 5 to 50 wt %, based on the carbon material.
As explained previously, in this optional embodiment, the carbon material according to the invention may also contain graphite. The carbon material preferably contains graphite in molar amounts of 1 to 50 mol %, preferably 5 to 40 mol %, based on the carbon material in this embodiment, the graphite may be present in mass-based amounts of 0.001 to 50 wt %, in particular 0.01 to 45 wt %, preferably 0.1 to 40 wt %, especially preferably 1 to 40 wt %, based on the carbon material. Graphite particles having average particle sizes (D50) in the range of 0.1 to 200 μm, in particular 1 to 100 μm, are generally used for this purpose. The BET surface area of the graphite used may vary in the range of 1 to 75 m2/g especially 2 to 50 m2/g, preferably 5 to 30 m2/g, especially preferably 10 to 20 m2/g. Those skilled in the art are familiar with graphites that may be used to improve the electrical conductivity. These products are available commercially.
In addition, it is possible to provide for the carbon material according to the invention to optionally contain at least one conductivity-improving agent, in particular a conductive carbon black. In this embodiment, the conductivity-improving agent in particular conductive carbon black may be present in molar amounts of 1 to 20 mol preferably 3 to 10 mol %, based on the carbon material. The conductivity-improving agent, especially the conductive carbon black, is usually present in mass-based amounts of 0.001 to 20 wt %, especially 0.01 to 15 wt %, preferably 0.1 to 10 wt %, based on the carbon material. Those skilled in the art are familiar with conductivity-improving agents that may be used for this purpose, in particular conductive carbon blacks, which are also available commercially. Conductivity-improving agents in particular conductive carbon blacks having average particle sizes (D50) in the range of 1 to 1.00 nm, in particular 20 to 60 nm, preferably 30 to 50 nm are advantageously used. Conductivity-improving agents suitable for use according to the invention, in particular conductive carbon blacks have BET surface areas in the range of 10 to 200 m2/g especially 50 to 80 m2/g, preferably 55 to 70 m2/g.
The carbon material according to the invention is characterized by a good electrical conductivity. The electrical conductivity of the carbon material according to the invention is usually in the range of 100 to 106 S/m especially 5·100 to 105 S/m. The conductivity of the carbon material according to the invention especially amounts to at least 100 S/m especially at least 103 S/m, preferably at least 104 S/m.
In addition, the present invention—according to a third aspect of the invention—relates to the use of the carbon material according to the invention as an anode material especially for lithium-ion batteries and/or for producing an anode material especially for lithium-ion batteries.
Another subject matter of the present invention—according to a fourth aspect of the present invention—is an anode material which contains the carbon material according to the present invention as described above.
According to a special embodiment, it is possible to provide for the anode material according to the present invention to be made exclusively of the carbon material according to the invention. This is the case in particular when the carbon material according to the invention is processed into molded bodies suitable for use as anodes and also has a sufficient mechanical stability.
Alternatively, however, it is also possible to provide for the carbon material according to the invention to be processed together with other components in particular graphite and/or conductivity-improving agents in particular conductive carbon black and/or binders to form an anode material according to the present invention, which is suitable in particular as an anode material for lithium-ion batteries.
An anode material according to the present invention which is suitable in this context may contain in particular
    • a carbon material according the invention as described above especially in amounts of 5 to 100 wt %, especially 10 to 95 wt %,
    • optionally graphite especially in amounts of 0.001 to 50 wt %, especially 0.01 to 45 wt %, preferably 0.1 to 40 wt %, especially preferably 1 to 40 wt %,
    • optionally at least one conductivity-improving agent, especially conductive carbon black especially in amounts of 0.001 to 20 wt %, especially 0.01 to 15 wt %, preferably 0.1 to 10 wt %,
    • optionally at least one preferably organic binder especially in amounts of 0.01 to 30 wt %, especially 0.1 to 25 wt %, preferably 0.5 to 15 wt %, especially preferably 1 to 1.0 wt %,
      wherein all the aforementioned amounts for percent by weight are based on the anode material and yield a total of 100 wt %.
In this aforementioned embodiment, such graphites and conductivity-improving agents especially conductive carbon blacks as those described previously may be used. To avoid unnecessary repetition, reference can be made to the preceding discussion in this regard, such that the statements made there apply to this aspect of the invention accordingly.
Those skilled in the art are familiar with binders, in particular organic binders, suitable for use according to the invention, as such. The binders may be any binders that permanently bind and/or hold together the aforementioned components. Preferred binders include polymeric binders preferably polyvinylidene fluoride, polytetrafluoroethylene or polyolefins, especially preferably thermoplastic elastomers in particular ethylene-propylene-diene terpolymers. Gelatin or modified cellulose may also be used as binders.
The anode material according to the invention is characterized by a good electrical conductivity which is in particular in the range of 101 to 105 S/m especially 5·101 to 104 S/m. In particular the anode material according to the invention is characterized by a conductivity of at least 101 S/m especially at least 102 S/m preferably at least 103 S/m.
Finally the subject matter of the present invention—according to a fifth aspect of the present invention—is a battery especially a lithium-ion battery preferably in the form of an accumulator, comprising an anode material according to the present invention as defined above and/or a carbon material according to the present invention as defined above.
For additional details regarding the other aspects of the present invention, reference can be made to the preceding discussion regarding the first aspect of the invention and vice-versa to avoid unnecessary repetition, and these statements then apply accordingly with respect to the other aspects of the invention.
Within the scope of the present invention, thus porous silicon- and/or tin-containing products and/or materials which are suitable as the anode material for lithium-ion batteries, in particular are made available. The subject matter of the invention is thus a porous to highly porous material for use as anode material in lithium-ion batteries.
Crystalline silicon nanoparticles, silicon/tin nanocomposite particles, nanoparticies based on silicon/tin alloys or tin nanoparticles produced by gas-phase synthesis or the like, for example, for the aforementioned purpose may typically be dispersed homogeneously in a monomer with subsequent polymerization or a polymer and then polymerized.
It is typically possible to proceed as described below within the scope of the present invention.
Crystalline nanoparticles of silicon and/or tin for the material according to the invention may first be dispersed homogeneously in a monomer which is then polymerized in situ in the presence of the silicon and/or tin or alternatively may be dispersed homogeneously in a polymer (organic). As explained previously, in the case of the monomer, the latter is then polymerized.
The polymers are processed further, for example, to molded articles such as spheres, wafers, blocks or more complex structures and then pyrolyzed thus yielding a carbon species with a large internal surface area (BET) (e.g., typically a few 100 m2/g to 2000 m2/g) and silicon, in and/or silicon/tin nanoparticles embedded therein. In the case of silicon nanoparticles, aggregated (so-called “hard agglomerates”) and unaggregated (so-called “soft agglomerates”) silicon with an average crystallite size between 1 and 100 nm is especially suitable. Silicon with an average crystallite size between 5 and 50 nm is most especially suitable. The average crystallite size can determined, for example, from histograms with transmission electron micrographs and/or from x-ray diffractograms as well as—in the case of the unaggregated powder—from the BET surface area.
To disperse the silicon, tin and/or silicon/tin nanoparticies in organic monomer or polymers, it is advantageous to first functionalize the particle surface for the purpose of hydrophobization. For this purpose, reactive silanes, for example, may be used for functionalization, chlorosilanes and hexamethyldisilazane being especially preferred, chlorosilanes of the general formulas SiClxR4-x where x=1 to 3, where R is an organic radical preferably with the general formula CnH(2n+1) most especially preferably with n=1 to 6 are preferred for functionalizing.
The silicon, tin and/or silicon/tin nanoparticles functionalized in this way can be bound by dispersion of these particles in a liquid/viscous monomer or polymer, for example, by stirring, kneading, milling in particular in ball mills, ultrasound, extrusion, etc.
Monomers and/or polymers that may be especially suitable for use according to the invention include organic compounds which do not contain any chemically bound oxygen in particular (poly) vinyl chloride, (poly)styrene, (poly)tetrafluoroethylene, (poly)ethylene and (poly) propylene; (poly) styrene is especially suitable, preferably with divinylbenzene as the crosslinking agent.
The silicon and/or tin and/or silicon/tin powder may be nominally undoped or may have a p- or n-type doping of up to 1021/cm3. Elements of Main Groups 3 and 5 are preferred (new nomenclature: group 13 and 15) of the periodic system of elements as well as elements from the iron group and especially preferably boron, aluminum, phosphorus and/or iron.
According to the invention, it is possible to produce mechanically strong materials which are even directly accessible in the form of ready-to-use electrodes so that, in the production of anodes, it is possible to completely eliminate the addition of a binder, organic in particular (usually a few weight percent) for production of mechanically strong electrodes.
Another possibility for producing the actual anodes starting from the emitted anode material is to also add graphite and/or conductive carbon black to the dispersion of monomer and/or polymer and silicon, tin and/or silicon/tin nanoparticles in order to improve the uptake capacity for lithium and to improve the electrical conductivity. The addition of graphite may typically amount to 1 to 50 mol %, preferably 5 to 40 mol %, based on the material according to the invention. The addition of conductive carbon black may amount to typically 1 to 20 mol %, preferably 3 to 10 mol %, based on the material according to the invention.
The silicon and/or tin content in the material according to the invention may typically be varied in a wide range. For example, a composition may contain 5 to 90 mol %, preferably 20 to 70 mol % silicon and/or tin based on the material according to the invention.
Additional embodiments, modifications and variations of the present invention are readily apparent and implementable for those skilled in the art in reading the description without going beyond the scope of the present invention.
The following exemplary embodiments are presented only for illustration of the present invention but without limiting the present invention thereto.
EXEMPLARY EMBODIMENTS Production of Silicon- and/or Tin-Containing Anode Materials According to the Invention
10 g of a surface-oxidized silicon obtained from microwave synthesis and having a BET surface area of 200 m2/g is mixed with 100 mL hexamethyldisilazane in a round-bottomed flask while stirring vigorously, stirring under nitrogen at a slight vacuum (approximately 900 mbar absolute) until no more ammonia is detectable in the gas phase going over. Next the excess hexamethyldisilazane is distilled off in vacuo.
The silicon powder functionalized in this way is dispersed in 1.00 mL styrene with the help of an ultrasound generator, and then 5 g divinylbenzene and 5 g dibenzoyl peroxide are added one after the other to the dispersion. The suspension is heated in a boiling water bath for 30 minutes while stirring, poured into a mold and cooled.
100 g of the resulting solids are then reduced in size and mixed with 200 mL concentrated sulfuric acid in a round-bottomed flask. The suspension is heated to 160° C. for 30 minutes while stirring vigorously, cooled and filtered.
The filter residue is transferred to a tubular oven and pyrolyzed at 750° C. for 3 hours under nitrogen.
The resulting material is then processed together with a binder and optionally together with graphite and/or conductive carbon blacks to form anodes for lithium-ion batteries.
Tin-based and/or silicon/tin-based anode materials are prepared by a comparable method, using as starting materials surface-oxidized tin composite and/or silicon/tin, produced from microwave synthesis as the starting materials instead of silicon, in deviation from the preceding exemplary embodiment.

Claims (7)

The invention claimed is:
1. A method for producing an electrically conductive porous silicon- and/or tin-containing material suitable for the production of anode materials and lithium-ion batteries, wherein:
(i) silicon nanoparticles and/or tin nanoparticles and/or silicon/tin nanoparticles are introduced into a polymer matrix based on at least one organic polymer in a first process step, wherein the silicon nanoparticles and/or tin nanoparticles and/or silicon/tin nanoparticles are subjected to a surface modification by alkylsilyl group functionalization before being introduced into the polymer matrix, and
(ii) then in a second process step, the polymer matrix containing the silicon and/or tin and/or silicon/tin nanoparticles is carbonized to carbon, wherein the resulting carbon material has a BET surface area of 100 to 1,750 m2/g.
2. The method according to claim 1, wherein an electrically conductive porous carbon material with the silicon nanoparticles and/or tin nanoparticles and/or silicon/tin nanoparticles intercalated therein is produced and wherein the silicon nanoparticles and/or tin nanoparticles and/or silicon/tin nanoparticles have an average particle size in the range of 1 to 1,000 nm.
3. The method according to claim 1, wherein the silicon nanoparticles and/or tin nanoparticles and/or silicon/tin nanoparticles are crystalline with a crystallinity of at least 70% and wherein the silicon nanoparticles and/or tin nanoparticles and/or silicon/tin nanoparticles have a BET surface area in the range from 1 to 2,000 m2/g.
4. The method according to claim 1, wherein the silicon nanoparticles and/or tin nanoparticles and/or silicon/tin nanoparticles contain at least one doping element comprising a p-type and/or n-type doping, where the at least one doping element is selected from the group consisting of boron, aluminum, phosphorus and/or iron as well as mixtures thereof.
5. The method according to claim 1, wherein the at least one organic polymer does not contain any chemically bound oxygen, and wherein the at least one organic polymer is selected from the group consisting of polyvinyl chloride, polyacrylonitrile, polystyrene, polytetrafluoroethylene, polyethylene and polypropylene and mixtures thereof.
6. The method according to claim 1, wherein the carbonization is performed under at least essentially inert conditions in the absence of oxygen and wherein the carbonization is performed at temperatures in the range from 300 to 2,000° C. for a period from 0.1 to 20 hours.
7. The method according to claim 1, wherein graphite and/or at least one conductivity improving agent is added in the course of the process.
US13/054,193 2008-07-15 2009-07-14 Intercalation of silicon and/or tin into porous carbon substrates Expired - Fee Related US8945431B2 (en)

Applications Claiming Priority (7)

Application Number Priority Date Filing Date Title
DE102008033097.3 2008-07-15
DE102008033097 2008-07-15
DE102008033097 2008-07-15
DE102008045231 2008-08-30
DE102008045231 2008-08-30
DE102008045231.9 2008-08-30
PCT/EP2009/005110 WO2010006763A1 (en) 2008-07-15 2009-07-14 Intercalation of silicon and/or tin into porous carbon substrates

Publications (2)

Publication Number Publication Date
US20110311873A1 US20110311873A1 (en) 2011-12-22
US8945431B2 true US8945431B2 (en) 2015-02-03

Family

ID=41091756

Family Applications (1)

Application Number Title Priority Date Filing Date
US13/054,193 Expired - Fee Related US8945431B2 (en) 2008-07-15 2009-07-14 Intercalation of silicon and/or tin into porous carbon substrates

Country Status (6)

Country Link
US (1) US8945431B2 (en)
EP (1) EP2303774B1 (en)
JP (1) JP5390609B2 (en)
KR (1) KR101441447B1 (en)
CN (1) CN102089240B (en)
WO (1) WO2010006763A1 (en)

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140349183A1 (en) * 2012-02-28 2014-11-27 Nexeon Limited Structured silicon particles
US10008716B2 (en) 2012-11-02 2018-06-26 Nexeon Limited Device and method of forming a device
US10077506B2 (en) 2011-06-24 2018-09-18 Nexeon Limited Structured particles
US10090513B2 (en) 2012-06-01 2018-10-02 Nexeon Limited Method of forming silicon
US10326136B2 (en) 2015-09-29 2019-06-18 GM Global Technology Operations LLC Porous carbonized composite material for high-performing silicon anodes
US10388948B2 (en) 2012-01-30 2019-08-20 Nexeon Limited Composition of SI/C electro active material
US10396355B2 (en) 2014-04-09 2019-08-27 Nexeon Ltd. Negative electrode active material for secondary battery and method for manufacturing same
US10424786B1 (en) 2018-12-19 2019-09-24 Nexeon Limited Electroactive materials for metal-ion batteries
US10476072B2 (en) 2014-12-12 2019-11-12 Nexeon Limited Electrodes for metal-ion batteries
US10508335B1 (en) 2019-02-13 2019-12-17 Nexeon Limited Process for preparing electroactive materials for metal-ion batteries
US10522824B2 (en) 2014-07-23 2019-12-31 Nexeon Ltd Method for preparing silicon-based active material particles for secondary battery and silicon-based active material particles
US10586976B2 (en) 2014-04-22 2020-03-10 Nexeon Ltd Negative electrode active material and lithium secondary battery comprising same
US10797303B2 (en) 2015-03-26 2020-10-06 Nexeon Ltd Silicon-based anode active material and preparation method therefor
US10797312B2 (en) 2014-12-31 2020-10-06 Nexeon Ltd. Silicon-based anode active material and method for manufacturing same
US10964940B1 (en) 2020-09-17 2021-03-30 Nexeon Limited Electroactive materials for metal-ion batteries
US11011748B2 (en) 2018-11-08 2021-05-18 Nexeon Limited Electroactive materials for metal-ion batteries
US11127945B2 (en) 2016-06-14 2021-09-21 Nexeon Limited Electrodes for metal-ion batteries
US11165054B2 (en) 2018-11-08 2021-11-02 Nexeon Limited Electroactive materials for metal-ion batteries
US11590568B2 (en) 2019-12-19 2023-02-28 6K Inc. Process for producing spheroidized powder from feedstock materials
US11633785B2 (en) 2019-04-30 2023-04-25 6K Inc. Mechanically alloyed powder feedstock
US11717886B2 (en) 2019-11-18 2023-08-08 6K Inc. Unique feedstocks for spherical powders and methods of manufacturing
US11839919B2 (en) 2015-12-16 2023-12-12 6K Inc. Spheroidal dehydrogenated metals and metal alloy particles
US11855278B2 (en) 2020-06-25 2023-12-26 6K, Inc. Microcomposite alloy structure
US11905593B2 (en) 2018-12-21 2024-02-20 Nexeon Limited Process for preparing electroactive materials for metal-ion batteries
US11919071B2 (en) 2020-10-30 2024-03-05 6K Inc. Systems and methods for synthesis of spheroidized metal powders
US11963287B2 (en) 2021-09-20 2024-04-16 6K Inc. Systems, devices, and methods for starting plasma

Families Citing this family (65)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5495887B2 (en) * 2009-04-28 2014-05-21 株式会社デンソー Negative electrode for non-aqueous electrolyte battery and non-aqueous electrolyte battery
US20110086756A1 (en) * 2010-12-20 2011-04-14 Gao hong-jun Method for preparing silicon intercalated monolayer graphene
KR101264324B1 (en) * 2011-01-04 2013-05-22 한국전기연구원 Process for producing Sn-based nanocomposite anode material for lithium secondary battery and lithium secondary battery including the same
JP2014525651A (en) * 2011-08-19 2014-09-29 ウィリアム・マーシュ・ライス・ユニバーシティ Anode battery material and manufacturing method thereof
KR101948125B1 (en) * 2011-08-31 2019-02-14 고쿠리츠다이가쿠호진 도호쿠다이가쿠 Si/C COMPOSITE MATERIAL, METHOD FOR MANUFACTURING SAME, AND ELECTRODE
DE102011112948B3 (en) * 2011-09-13 2012-12-06 Gottfried Wilhelm Leibniz Universität Hannover Process for improving the electrical conductivity of inorganic particles and their use
FR2980191B1 (en) * 2011-09-20 2014-10-24 Commissariat Energie Atomique PROCESS FOR PRODUCING A SILICON / CARBON COMPOSITE MATERIAL AND THE USE OF SUCH A MATERIAL
WO2013051673A1 (en) * 2011-10-07 2013-04-11 帝人株式会社 Lithium ion secondary battery anode and lithium ion secondary battery
CN102412391A (en) * 2011-10-20 2012-04-11 浙江大学 Preparation method of tin carbon composite nano-material for lithium ion battery cathode
KR20130059472A (en) 2011-11-28 2013-06-07 삼성에스디아이 주식회사 Negative active material and lithium battery containing the material
CN102447112B (en) * 2011-11-30 2014-07-30 奇瑞汽车股份有限公司 Silicon-carbon composite material, preparation method thereof and cathode material containing same as well as lithium ion battery
DE102011088533A1 (en) * 2011-12-14 2013-06-20 Robert Bosch Gmbh Electrode, method for producing an electrode and energy storage comprising an electrode
KR101875950B1 (en) * 2011-12-20 2018-07-12 한국과학기술원 Manufacturing method for anode active material of lithium secondary battery comprising carbon composite nano particle with silicon porosity, anode active material of lithium secondary battery manufactured by the same, and lithium secondary battery comprising the same
WO2013120011A1 (en) 2012-02-09 2013-08-15 Energ2 Technologies, Inc. Preparation of polymeric resins and carbon materials
KR101400341B1 (en) * 2012-02-23 2014-06-19 포항공과대학교 산학협력단 Binder-free Ge Nanoparticles/Carbon Hybrids for Anode Materials of Advanced Lithium-Polymer Batteries with High Capacity and Rate Capability
DE102012202968A1 (en) 2012-02-28 2013-08-29 Sgl Carbon Se Process for the preparation of coated active materials and their use for batteries
JP2013209256A (en) * 2012-03-30 2013-10-10 Mitsubishi Chemicals Corp Composite carbon material, method of manufacturing the same, and negative electrode and power storage device using the composite carbon material
JP5494712B2 (en) * 2012-04-13 2014-05-21 株式会社豊田自動織機 Negative electrode active material for nonaqueous electrolyte secondary battery, method for producing the same, negative electrode for nonaqueous electrolyte secondary battery, nonaqueous electrolyte secondary battery, and vehicle
DE102012213595A1 (en) 2012-08-01 2014-05-15 Technische Universität Dresden Process for the production of porous carbon
US10374221B2 (en) 2012-08-24 2019-08-06 Sila Nanotechnologies, Inc. Scaffolding matrix with internal nanoparticles
US20140272592A1 (en) 2013-03-14 2014-09-18 Energ2 Technologies, Inc. Composite carbon materials comprising lithium alloying electrochemical modifiers
WO2014141732A1 (en) * 2013-03-14 2014-09-18 Dic株式会社 Metal tin-carbon complex, method for producing said complex, negative electrode active material for non-aqueous lithium secondary batteries which is produced using said complex, negative electrode for non-aqueous lithium secondary batteries which comprises said negative electrode active material, and non-aqueous lithium secondary battery
KR101598659B1 (en) * 2013-03-22 2016-03-03 포항공과대학교 산학협력단 Facile Synthesis of Tin-Carbon-Silica Nanocomposites for Anode Materials in Lithium-ion Batteries
DE102013211388A1 (en) * 2013-06-18 2014-12-18 Wacker Chemie Ag Electrode material and its use in lithium-ion batteries
DE102013215257A1 (en) * 2013-08-02 2015-02-05 Wacker Chemie Ag Process for comminuting silicon and use of comminuted silicon in a lithium-ion battery
DE102013219308A1 (en) * 2013-09-25 2015-03-26 Robert Bosch Gmbh Electrode composition, electrode and lithium ion accumulator
WO2015051309A1 (en) * 2013-10-04 2015-04-09 Board Of Trustees Of The Leland Stanford Junior University Large-volume-change lithium battery electrodes
US10195583B2 (en) 2013-11-05 2019-02-05 Group 14 Technologies, Inc. Carbon-based compositions with highly efficient volumetric gas sorption
DE102014202156A1 (en) 2014-02-06 2015-08-06 Wacker Chemie Ag Si / G / C composites for lithium-ion batteries
KR102347131B1 (en) 2014-03-14 2022-01-04 그룹14 테크놀로지스, 인코포레이티드 Novel methods for sol-gel polymerization in absence of solvent and creation of tunable carbon structure from same
KR101572364B1 (en) * 2014-03-19 2015-11-26 오씨아이 주식회사 Carbon-silicon composite and negative electrode for lithium secondary battery and lithium secondary battery using the same
EP3157081B1 (en) 2014-06-13 2020-08-05 LG Chem, Ltd. Silicon-carbon composite, negative electrode comprising same, secondary battery using silicon-carbon composite, and method for preparing silicon-carbon composite
KR101609459B1 (en) * 2014-07-03 2016-04-06 오씨아이 주식회사 Carbon-silicon composite and manufacturing mehtod of the same
KR101679367B1 (en) 2014-08-25 2016-11-24 서강대학교산학협력단 Carbon-silicon composite structure and preparing method of the same
KR101606647B1 (en) * 2014-09-03 2016-03-28 오씨아이 주식회사 Carbon-silicon composite and manufacturing mehtod of the same
JP6771900B2 (en) * 2015-02-09 2020-10-21 大阪瓦斯株式会社 Method for manufacturing negative electrode material for lithium secondary battery, method for improving lithium secondary battery, and its charge / discharge characteristics and cycle characteristics
KR101761004B1 (en) * 2015-06-08 2017-07-25 오씨아이 주식회사 Copomsition for preparing silicon-carbon composite, silicon-carbon composite, electrode for secondary battery including the same and method for manufacturing the same
US10270094B2 (en) * 2015-07-06 2019-04-23 Mossey Creek Technologies, Inc. Porous sintered superstructure with interstitial silicon for use in anodes for lithium batteries
KR101796249B1 (en) * 2015-07-09 2017-11-10 경희대학교 산학협력단 Anode active material for secondary battery and method of preparing the same
CN105070517A (en) * 2015-07-30 2015-11-18 上海应用技术学院 Ellipsoidal nitrogen-boron-phosphorus-doped mesoporous carbon and preparation method and application thereof
WO2017030995A1 (en) 2015-08-14 2017-02-23 Energ2 Technologies, Inc. Nano-featured porous silicon materials
EP3341990A1 (en) 2015-08-28 2018-07-04 Energ2 Technologies, Inc. Novel materials with extremely durable intercalation of lithium and manufacturing methods thereof
US20170149055A1 (en) * 2015-11-19 2017-05-25 Panasonic Intellectual Property Management Co., Ltd. Lithium-ion secondary battery
DE102016202459A1 (en) 2016-02-17 2017-08-17 Wacker Chemie Ag Core-shell composite particles
DE102016202458A1 (en) 2016-02-17 2017-08-17 Wacker Chemie Ag Process for producing Si / C composite particles
CN108701822A (en) * 2016-02-29 2018-10-23 日本电气株式会社 Negative electrode active material and use its lithium rechargeable battery
US11152608B2 (en) 2016-05-31 2021-10-19 The Regents Of The University Of California Modified silicon particle electrodes and methods
KR102580237B1 (en) 2016-07-04 2023-09-20 삼성전자주식회사 Composite electrode active material, lithium battery including the same, and method of preparing the composite electrode active material
KR20180027022A (en) * 2016-09-05 2018-03-14 지에스에너지 주식회사 Anode active material for secondary battery and preparation method thereof
DE112016002671T5 (en) 2016-10-19 2018-07-19 Tec One Co., Ltd. Carbon-silicon composite, negative electrode, secondary battery, and carbon-silicon composite manufacturing method
DE102016224039A1 (en) * 2016-12-02 2018-06-07 Robert Bosch Gmbh Anode active material particles with artificial SEI layer by means of graft-to-polymerization
JP7376360B2 (en) 2017-03-09 2023-11-08 グループ１４・テクノロジーズ・インコーポレイテッド Degradation of silicon-containing precursors on porous scaffold materials
KR20180130182A (en) * 2017-05-29 2018-12-07 에스케이이노베이션 주식회사 Lithium secondary battery
GB2563455B (en) 2017-06-16 2019-06-19 Nexeon Ltd Particulate electroactive materials for use in metal-ion batteries
CN109309203A (en) 2017-07-26 2019-02-05 中能中科（天津）新能源科技有限公司 Nano carbon particle-stephanoporate framework composite material, its lithium metal compound, their preparation method and application
CN109309200B (en) 2017-07-26 2021-02-26 中能中科（天津）新能源科技有限公司 Metal lithium-framework carbon composite material with hydrophobic coating layer, and preparation method and application thereof
CN110556519A (en) * 2018-06-04 2019-12-10 广州汽车集团股份有限公司 Silicon cathode material, silicon cathode and preparation method of silicon cathode
DE102018221839A1 (en) 2018-12-14 2020-06-18 Sgl Carbon Se Carbon-silicon composite material
CN109920990B (en) * 2019-03-01 2022-02-11 贵州大学 Preparation method for preparing silicon-metal-carbon composite material by microwave
US20230231111A1 (en) * 2020-05-28 2023-07-20 Showa Denko K.K. Composite carbon particles and use thereof
US11335903B2 (en) 2020-08-18 2022-05-17 Group14 Technologies, Inc. Highly efficient manufacturing of silicon-carbon composites materials comprising ultra low z
US11639292B2 (en) 2020-08-18 2023-05-02 Group14 Technologies, Inc. Particulate composite materials
US11174167B1 (en) 2020-08-18 2021-11-16 Group14 Technologies, Inc. Silicon carbon composites comprising ultra low Z
JPWO2022270539A1 (en) * 2021-06-22 2022-12-29
EP4235868A1 (en) * 2022-02-23 2023-08-30 Evonik Operations GmbH Silicon-containing anode material and silicon-containing electron-supplying fuel

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020164479A1 (en) * 2001-03-02 2002-11-07 Keiko Matsubara Carbonaceous material and lithium secondary batteries comprising same
US20030096163A1 (en) * 2001-10-29 2003-05-22 Masahide Miyake Non aqueous electrolyte secondary battery
US6605386B1 (en) * 1998-12-02 2003-08-12 Matsushita Electric Industrial Co., Ltd. Non-aqueous electrolyte secondary battery comprising composite particles
US20050233213A1 (en) * 2004-03-08 2005-10-20 Lee Sang-Min Negative active material for a rechargeable lithium battery, a method of preparing the same, and a rechargeable lithium battery comprising the same
US20060040182A1 (en) * 2003-03-26 2006-02-23 Canon Kabushiki Kaisha Electrode material for lithium secondary battery and electrode structure having the electrode material
US20060172200A1 (en) * 2005-02-03 2006-08-03 Jae-Gu Yoon Organic electrolytic solution and lithium battery employing the same
US20070281216A1 (en) * 2004-04-01 2007-12-06 Frank-Martin Petrat Nanoscalar Silicon Particles In Negative Electrode Materials For Use In Lithium-Ion Batteries
WO2008088050A1 (en) * 2007-01-19 2008-07-24 Stella Chemifa Corporation Electrical storage device

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0819263B2 (en) * 1988-02-08 1996-02-28 東レ・ダウコーニング・シリコーン株式会社 Flowability improver for negatively chargeable resin powder
JP2000328080A (en) * 1999-03-12 2000-11-28 Shin Etsu Chem Co Ltd Agent for low friction treatment of seat belt
JP3897709B2 (en) * 2002-02-07 2007-03-28 日立マクセル株式会社 Electrode material, method for producing the same, negative electrode for non-aqueous secondary battery, and non-aqueous secondary battery
AU2003274763A1 (en) * 2002-10-29 2004-05-25 Sony Corporation Rechargeable electrochemical cell
JP3995050B2 (en) * 2003-09-26 2007-10-24 Ｊｆｅケミカル株式会社 Composite particles for negative electrode material of lithium ion secondary battery and method for producing the same, negative electrode material and negative electrode for lithium ion secondary battery, and lithium ion secondary battery
KR100578871B1 (en) 2004-03-08 2006-05-11 삼성에스디아이 주식회사 Negative active material for lithium secondary battery, method of preparing same, and lithium secondary battery comprising same
JP4998662B2 (en) * 2004-07-30 2012-08-15 信越化学工業株式会社 Si-C-O-based composite, production method thereof, and negative electrode material for non-aqueous electrolyte secondary battery
JP4578400B2 (en) * 2005-12-26 2010-11-10 株式会社トクヤマ Toner external additive for electrophotography
KR100830612B1 (en) * 2006-05-23 2008-05-21 강원대학교산학협력단 Negative active material for lithium secondary battery, method of preparing same, and lithium secondary battery comprising same

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6605386B1 (en) * 1998-12-02 2003-08-12 Matsushita Electric Industrial Co., Ltd. Non-aqueous electrolyte secondary battery comprising composite particles
US20020164479A1 (en) * 2001-03-02 2002-11-07 Keiko Matsubara Carbonaceous material and lithium secondary batteries comprising same
US20030096163A1 (en) * 2001-10-29 2003-05-22 Masahide Miyake Non aqueous electrolyte secondary battery
US20060040182A1 (en) * 2003-03-26 2006-02-23 Canon Kabushiki Kaisha Electrode material for lithium secondary battery and electrode structure having the electrode material
US20050233213A1 (en) * 2004-03-08 2005-10-20 Lee Sang-Min Negative active material for a rechargeable lithium battery, a method of preparing the same, and a rechargeable lithium battery comprising the same
US20070281216A1 (en) * 2004-04-01 2007-12-06 Frank-Martin Petrat Nanoscalar Silicon Particles In Negative Electrode Materials For Use In Lithium-Ion Batteries
US20060172200A1 (en) * 2005-02-03 2006-08-03 Jae-Gu Yoon Organic electrolytic solution and lithium battery employing the same
WO2008088050A1 (en) * 2007-01-19 2008-07-24 Stella Chemifa Corporation Electrical storage device
US20100099030A1 (en) * 2007-01-19 2010-04-22 Stella Chemifa Corporation Electric storage element

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Stewart et al., "Direct Covalent Grafting of Conjugated Molecules onto Si, GaAs, and Pd Surfaces from Aryldiazonium Salts," web published Dec. 16, 2003, J. Am. Chem. Soc., 2004 vol. 126, pp. 370-378. *

Cited By (35)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10822713B2 (en) 2011-06-24 2020-11-03 Nexeon Limited Structured particles
US10077506B2 (en) 2011-06-24 2018-09-18 Nexeon Limited Structured particles
US10388948B2 (en) 2012-01-30 2019-08-20 Nexeon Limited Composition of SI/C electro active material
US20140349183A1 (en) * 2012-02-28 2014-11-27 Nexeon Limited Structured silicon particles
US10103379B2 (en) * 2012-02-28 2018-10-16 Nexeon Limited Structured silicon particles
US10090513B2 (en) 2012-06-01 2018-10-02 Nexeon Limited Method of forming silicon
US10008716B2 (en) 2012-11-02 2018-06-26 Nexeon Limited Device and method of forming a device
US10396355B2 (en) 2014-04-09 2019-08-27 Nexeon Ltd. Negative electrode active material for secondary battery and method for manufacturing same
US10693134B2 (en) 2014-04-09 2020-06-23 Nexeon Ltd. Negative electrode active material for secondary battery and method for manufacturing same
US10586976B2 (en) 2014-04-22 2020-03-10 Nexeon Ltd Negative electrode active material and lithium secondary battery comprising same
US11196042B2 (en) 2014-07-23 2021-12-07 Nexeon Ltd Method for preparing silicon-based active material particles for secondary battery and silicon-based active material particles
US10522824B2 (en) 2014-07-23 2019-12-31 Nexeon Ltd Method for preparing silicon-based active material particles for secondary battery and silicon-based active material particles
US10476072B2 (en) 2014-12-12 2019-11-12 Nexeon Limited Electrodes for metal-ion batteries
US10797312B2 (en) 2014-12-31 2020-10-06 Nexeon Ltd. Silicon-based anode active material and method for manufacturing same
US10797303B2 (en) 2015-03-26 2020-10-06 Nexeon Ltd Silicon-based anode active material and preparation method therefor
US10326136B2 (en) 2015-09-29 2019-06-18 GM Global Technology Operations LLC Porous carbonized composite material for high-performing silicon anodes
US11839919B2 (en) 2015-12-16 2023-12-12 6K Inc. Spheroidal dehydrogenated metals and metal alloy particles
US11127945B2 (en) 2016-06-14 2021-09-21 Nexeon Limited Electrodes for metal-ion batteries
US11695110B2 (en) 2018-11-08 2023-07-04 Nexeon Limited Electroactive materials for metal-ion batteries
US11688849B2 (en) 2018-11-08 2023-06-27 Nexeon Limited Electroactive materials for metal-ion batteries
US11165054B2 (en) 2018-11-08 2021-11-02 Nexeon Limited Electroactive materials for metal-ion batteries
US11011748B2 (en) 2018-11-08 2021-05-18 Nexeon Limited Electroactive materials for metal-ion batteries
US10424786B1 (en) 2018-12-19 2019-09-24 Nexeon Limited Electroactive materials for metal-ion batteries
US10938027B2 (en) 2018-12-19 2021-03-02 Nexeon Limited Electroactive materials for metal-ion batteries
US10658659B1 (en) 2018-12-19 2020-05-19 Nexeon Limited Electroactive materials for metal-ion batteries
US11715824B2 (en) 2018-12-19 2023-08-01 Nexeon Limited Electroactive materials for metal-ion batteries
US11905593B2 (en) 2018-12-21 2024-02-20 Nexeon Limited Process for preparing electroactive materials for metal-ion batteries
US10508335B1 (en) 2019-02-13 2019-12-17 Nexeon Limited Process for preparing electroactive materials for metal-ion batteries
US11633785B2 (en) 2019-04-30 2023-04-25 6K Inc. Mechanically alloyed powder feedstock
US11717886B2 (en) 2019-11-18 2023-08-08 6K Inc. Unique feedstocks for spherical powders and methods of manufacturing
US11590568B2 (en) 2019-12-19 2023-02-28 6K Inc. Process for producing spheroidized powder from feedstock materials
US11855278B2 (en) 2020-06-25 2023-12-26 6K, Inc. Microcomposite alloy structure
US10964940B1 (en) 2020-09-17 2021-03-30 Nexeon Limited Electroactive materials for metal-ion batteries
US11919071B2 (en) 2020-10-30 2024-03-05 6K Inc. Systems and methods for synthesis of spheroidized metal powders
US11963287B2 (en) 2021-09-20 2024-04-16 6K Inc. Systems, devices, and methods for starting plasma

Also Published As

Publication number Publication date
CN102089240A (en) 2011-06-08
JP5390609B2 (en) 2014-01-15
EP2303774A1 (en) 2011-04-06
KR20110052595A (en) 2011-05-18
US20110311873A1 (en) 2011-12-22
WO2010006763A1 (en) 2010-01-21
CN102089240B (en) 2016-06-08
EP2303774B1 (en) 2017-06-14
JP2011527982A (en) 2011-11-10
KR101441447B1 (en) 2014-09-17

Similar Documents

Publication Publication Date Title
US8945431B2 (en) Intercalation of silicon and/or tin into porous carbon substrates
Lin et al. Lithium–sulfur batteries: from liquid to solid cells
Wang et al. Nano active materials for lithium-ion batteries
KR101316413B1 (en) Electrically conductive nanocomposite material comprising sacrificial nanoparticles and open porous nanocomposites produced thereof
WO2020154235A1 (en) Silicon/graphene composite anode material and method to manufacture the same
KR20210079442A (en) Anode material with graphene-mxene-silicon of secondary battery and the method thereof
DE102009033251A1 (en) Producing an electrically conductive porous carbon material useful as a battery anode material comprises incorporating silicon and/or tin nanoparticles into a polymer matrix and carbonizing the product
CN108352510B (en) All-solid-state rechargeable lithium battery
US20120025147A1 (en) Method for preparing unique composition high performance anode materials for lithium ion batteries
KR20150006703A (en) Negative active material for rechargeabl lithium battery, composition for negative electrode including the same, and rechargeabl lithium battery
KR101478160B1 (en) Nano particle-graphene-carbon composites containing internally-formed graphene network, method for preparing the composite, and application thereof
KR102405622B1 (en) Anode material with graphene-cnt-silicon coreshell of secondary battery and the method thereof
US20220013765A1 (en) Graphitic carbon nitride materials and methods of making and use thereof
KR102405612B1 (en) Anode material with graphene-agnw-silicon of secondary battery and the method thereof
KR20210000983A (en) Composite Anode, and the lithium secondary battery comprising the same
Oh et al. Hierarchical Si hydrogel architecture with conductive polyaniline channels on sulfonated-graphene for high-performance Li ion battery anodes having a robust cycle life
Mao et al. Advanced Aqueous Zinc‐Ion Batteries Enabled by 3D Ternary MnO/Reduced Graphene Oxide/Multiwall Carbon Nanotube Hybrids
JP4968766B2 (en) Carbon material for negative electrode of lithium ion secondary battery and method for producing the same
KR101295974B1 (en) Method for preparing lithium manganese oxide positive active material for lithium ion secondary battery, positive active material prepared thereby, and lithium ion secondary battery including the same
KR101674736B1 (en) Lithium air secondary battery, and method of fabricating the same
KR101604003B1 (en) Anodes active material containing Si composite for lithium secondary batteries and its preparation method and lithium secondary batteries comprising the same
KR102388203B1 (en) Anode material with graphene-mxene-silicon of secondary battery and the method thereof
KR102405605B1 (en) Anode material with graphene-antimony-silicon of secondary battery and the method thereof
KR101693930B1 (en) Fabricating method of electrode for electrochemical device, electrode slurry, and electrode for electrochemical device fabricated thereby
Inamoto et al. Electrode performance of sulfur-doped vanadium pentoxide gel prepared by microwave irradiation for rechargeable magnesium batteries

Legal Events

Date Code Title Description
AS Assignment

Owner name: UNIVERSITAET DUISBURG-ESSEN, GERMANY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SCHULZ, CHRISTOF, DR;WIGGERS, HARTMUT, DR;SIGNING DATES FROM 20110113 TO 20110120;REEL/FRAME:033257/0689

STCF Information on status: patent grant

Free format text: PATENTED CASE

MAFP Maintenance fee payment

Free format text: PAYMENT OF MAINTENANCE FEE, 4TH YR, SMALL ENTITY (ORIGINAL EVENT CODE: M2551)

Year of fee payment: 4

FEPP Fee payment procedure

Free format text: MAINTENANCE FEE REMINDER MAILED (ORIGINAL EVENT CODE: REM.); ENTITY STATUS OF PATENT OWNER: SMALL ENTITY

LAPS Lapse for failure to pay maintenance fees

Free format text: PATENT EXPIRED FOR FAILURE TO PAY MAINTENANCE FEES (ORIGINAL EVENT CODE: EXP.); ENTITY STATUS OF PATENT OWNER: SMALL ENTITY

STCH Information on status: patent discontinuation

Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362

FP Lapsed due to failure to pay maintenance fee

Effective date: 20230203